I tried last night to change the clock on our oven, failed at this simple task, but in the process discovered a hitherto unknown “feature” of the device. By pressing and holding the clock button one enters “sabbath mode” in which the oven aids your observance by refusing to work. A google search for an apparent error code quickly solved the problem. The clock is actually set by pressing clock once and then up/down. It gives no indication that it is in clock-set mode.